Hey I'm Nick. I do concept art in many forums. I'm an art physics student so a lot of my work has started as hand drawn work. If you would like your suggestion for a weapon or something on the suggestion forums designed as a 3D model or drawn out, I can do it for you for a certain price (in ce) we can discuss over complexity. I will also do 2d concept art and fan art if you want, but I don't have many samples of that onine for a few reasons, but I will link some art I've done to show you that the skill is there.
3D art sample-
Judgment Concept (Severage) http://beastly-nikk.deviantart.com/gallery/#/d4uajun
Fine Art (to show abilities)
http://beastly-nikk.deviantart.com/gallery/#/d4ue2cb
Simple Example of my comic character, drawn on an Iphone
http://beastly-nikk.deviantart.com/gallery/#/d4ue2gb
(I draw comics so If you would like a comic drawn I can do that too. Its an older style of comics familiar to Calvin and Hobbes if you read that, which is my favorite ;D, I will add more later, this was a fast draw obviously)
Photoshop Concept
Very simple and fast example so I will add more later
Quake Attack Skill Concept http://beastly-nikk.deviantart.com/gallery/#/d4u7bt8
Fan Art -
I did this tonight pretty fast to show you an example of digital work I can do. I can do other styles too =p
http://beastly-nikk.deviantart.com/art/My-Spiral-Knight-292928409
Sketch Concept
This was a 2-5 minuet sketch for the grimalking http://beastly-nikk.deviantart.com/gallery/#/d4u7bt8
Most of these were done as a personal thing or just randomly for other people for free. If commissioned you can expect hire quality then the sketch of course and the photoshop concept. I will link more samples later.
*Updated*
Also here is a mobile concept I'm working on
http://beastly-nikk.deviantart.com/gallery/#/d4ugopi
http://beastly-nikk.deviantart.com/gallery/#/d4ugols